摘要
Duffing系统对特定信号敏感及对噪声免疫的特性,使其在微弱信号检测中有巨大潜在应用。待测信号首先通过锁相环电路得到信号的频率,再被输入混沌检测系统。在Duffing振子检测系统中,策动力变化时系统输出信号时序图呈现同步且规律性变化。据此可判断系统混沌状态,并得到精确的阈值,从而实现待测信号的检测。理论分析及仿真结果表明,较之传统做法,此方法可检测未知频率的信号,更易于实现且节省大量仿真时间,因此在实际应用中具有重大意义。
Duffing system is extremely sensitive to specific signals and immune against the noise.This feature has potential applications in weak signals detection.Firstly,the frequency of measured signal is obtained by phase locked loop circuit.Then the measured signal is put into the chaotic detection system.In Duffing system,the waveform of the output signals changes synchronized and regularly as the driving force varying.The method can be used to judge the state of chaotic systems and obtain the accurate threshold.Therefore the measured signals can be detected.Compared with the traditional methods,theoretical analysis and simulation results showed that the method can detect signals with unknown frequency,easier to be realized and saves a large amount of simulation time.Therefore,it is greatly significant in real application.
出处
《科学技术与工程》
北大核心
2014年第6期13-19,共7页
Science Technology and Engineering
基金
国家自然科学基金项目(61071196
61102131)
教育部新世纪优秀人才支持计划项目(NCET-10-0927)
信号与信息处理重庆市市级重点实验室建设项目(CSTC2009CA2003)
重庆市杰出青年基金项目(CSTC2011jjjq40002)
重庆市自然科学基金项目(CSTC2010BB2398
CSTC2010BB2409
CSTC2010BB2411
CSTC2012JJA40008)
重庆市教育委员会科研项目(KJ120525
KJ130524)
国家留学基金资助
关键词
混沌系统
微弱信号
锁相环
混沌阈值
chaotic systems
weak signal
phase locked loop
chaotic threshold
